Electrodes employing disposable electropods for cardiac instruments

ABSTRACT

This invention relates to disposable electrode pads which may be used with cardiac devices, such as ECG, defibrillator or pacemaker devices. The pads are in the form of a foil bag containing an electrolyte. The bags are easily rupturable so that the electrolyte is applied to the surface of the human body.

United States Patent [191 Funfstuck July 30, 1974 [54] ELECTRODESEMPLOYING DISPOSABLE 1,667,817 5/1928 Noishiki 128/417 ELECTROPODS FORCARDIAC 1,849,745 3/1932 Hoffman 128/418 INSTRUMENTS 2,943,627 7/1960Howell l28/DlG. 4 X 3,487,827 l/l970 Edmark [28/206 E [75] Inventor:Horst Funfstuck, Oxnard, Calif. 3,601,126 8/1971 Estes 128/417 2;:

3,602,216 8/1971 Moe l28/2.06 Asslgneel g Instruments, -1 Oxnard,3,702,613 1 mm Panico ct al. 1221/41? Filedi 1973 PrimaryExaminr-Richard A. Gaudet [21] App! 331,050 Assistant Examiner-Lee S.Cohen [52] US. Cl. l28/2.06 E, l28/DlG. 4, 128/417, [57] ABSTRACT [51]lm Cl 5" 2 This invention relates to disposable electrode pads 58] Fieid/2 06 E 2 i E DIG 4 which may be used with cardiac devices, such as ECG,E6 417 @4 6 1 defibrillator or pacemaker devices. The pads are in theform of a foil bag containing an electrolyte. The

bags are easily rupturable so that the electrolyte is ap- [56] g g gg gzplied to thesurface of the human body. 506,449 10/1893 Silsbce 128/1721l'Claim, 5 Drawing Figures BACKGROUND OF THE INVENTION In all of thecardiac devices such as E.C.G. defibrillator or pacemaker devices, it isnecessary to connect the device to the body of the patient by electrodesspaced from each other on the body. This requires that the electrodesmake electrical contact with the body of the patient. It is usual, inthis connection, to use creams and sometimes saline salt gauze padsapplied to the electrodes to insure adequate electrical contact betweenthe electrodes and the patient and to prevent Iocalized points ofcontact between the electrodes on the body. This requires preparation ofthe patient, when under some circumstances, time maybe'extremelycritical as for example when defibrillation or pacemaker pulses must beapplied. 4

STATEMENT OF THE INVENTION be mounted on the paddle'of the electrode andare easily removed and replaced when once used. The electrolyte may be asaline water or saline viscous of paste-like material or otherconductive material used in this art. The pads are attached to thepaddle surface by means of an adhesive backing on the side of the foilbag to be placed against the electrode paddle.

Various methods could be used for rupturing the foil bag; for example,the bag could have weak spots such as scoring formed in the foil so thatwhen the paddle places a pressure upon the pad the bag willrupture andapply the electrolyte so that good electrical contact is made with thepatient. Alternatively, a mechanical device may be attached to thepaddle so that the foil bag is ruptured and the electrolyte issues tocreate the conductive path.

In order to insure the successful application of the electrolyte betweenthe electrode surface and the body provide 1 may and preferably doprovide a sponge, which may be of plastic foam, which is saturated bythe electrolyte and which-is placed between the foil bag and the bodymember when the electrode is applied. This may be and preferably isattached to the side of the bag opposite to that to be placed againstthe electrode paddle.

DETAILED STATEMENT OF MY INVENTION This and other objects of myinvention will be further understood by reference to the figures ofwhich:

FIG. 1 is a schematic of a circuit which is one possible application ofmy invention.

' FIG. 2 shows one form of the electrode of my invention carrying thedisposable pad of my invention.

FIG. 3 is a fragmentary view of FIG. 2.

FIG. 4 shows a section of another and preferred form of electrodeshowing the application of the disposable pad of my invention.

FIG. 5 is an exploded view of the disposable pad of my invention. I

FIG. 1 shows a circuit for application of my invention to an ECG unit ora defibrillation unit or a combina tion of the two illustrating thatcombination. Other types of cardiac systems may be employed, forexample, the form'described'in Public Health Reports No. 11 November1966 at page 1,042 and 1,043.

The switch 1 may be'placed in any position but is conveniently mountedupon the electrode, for example, electrode 8 of the electrode pair 7 and8.The closing of the switch 1 actuates the relay 2 which actuates theswitches 3 and 4. As shown, theswitches are in position to connect thehigh voltage source to the condenser 5 to charge the condenser. Whenswitch I is closed, the relay. pulls the contact from position contacts3 and 4 to contact'6-and a pulse is applied to the electrodes 7 and 8.The E.C.G. unit 9 is connected to the electrodes 7 and 8m that the heartis monitored at all times and is protected by the capacitor and diodesand resistor system in junction box 10. Since the aforesaid system isnot a portion of my invention but merely illustrates onepossible use ofmy invention, it need not reduce the time and make the preparation ofthe patient more convenient.

FIG. 2 shows one illustration of an electrode using the disposable padof my invention. The pads 13 consists of a bag formed of a metallic foilsheet 1'] and 12 which are sealed at the edges at 14 by cementing,crimping or welding the outer edges together; The bag filled with anelectrically conductive material 15 such as a saline solution or with aconductive jelly or other equivalent electrically conductive liquid orsemi-liquid conductive material for example such as has been used toinsure electricalcontact between the electrode and the body. Methods offilling foil bags with material for example, ketchup or mustard, arewell known and may be used for this purpose.

The side to be placed against the electrode may be and preferably iscoated with an adhesive material for example, a pressure sensitiveadhesived for attachment of the bag to the underneath side of the paddleof the electrode. The lower side of the lower foil 12 is adhesivelyconnected to a sponge 16. The sponge 16 may be of any sponge sheetmaterial and in my preferred embodiment is a urethane foam or a similarrubber foam sheet. While not essential to my invention, a spongesaturated with the conductive fluid may be placed inside the bag formedat the foil sheets 11 and 12 with the edges of the foil sheets sealed toeach other.

As is illustrates in FIGS. 2 and 3, the pad may be adhesively mounted inthe electrode 7 or 8 which are 18 is bored with a bore 21 and the punch22 is mounted,

7 3- in the ring and carries a needle 23 mounted in the punch 22. Aneedle limit motion stop is provided in the form of a slot 23' which ismounted a stop pin 24 connected to the needle 23 so that when the head24' is depressed against the spring 25 the needle punctures the foilsheet 11 and 12 of the bag permitting the material in the bag tosaturate the sponge 16 when the electrode is pressed against the bodycompressing the bag. On reneedle having retracted, it will not injurethe patient when pressure is applied. As shown in the form illustratedin FIG. 2 the electrode is provided with a handle 17.

The form in FIG. 4 shows an alternative form. The electrode 8 is ahollow member made of plastic or other insulating material with a guarddisc 26 and carrying the switch, 1 with the suitable electricalconnections connected to the terminal 28. The electrode is connected bymeans of the electrode terminal 28 which makes contact with the metallicplate 29 to which foil bag is connected. In this case, the foils of thebag may be sufficiently weakened at suitable localities as by lease ofpressure on head 24' the needle retracts. The

scoring so that when pressure is applied to the electrode plate 30 theenvelope is compressed and stretched and ruptured at the weakenedportions on the surface. Rupture will occur in the foil 12 and permitthe fluid to escape to saturate the sponge 16.

I claim:

1. An electrode for electrocardiac machine comprising a metallic sheet,a handle to which said sheet is mounted, an electrical connectioninsulated from said handle and electrically connected to said metallicsheet, a closed foil bag having two sides, one side being mounted onsaid metallic sheet, an electrolyte in said bag, and a sponge connectedto the side of the bag opposite to the aforementioned side adhesivelyconnected on said metallic sheet, a retractable punch mounted on saidhandle adjoining said foil bag, and means connected to said punch formoving said punch through both sides of said foil bag, whereby saidpunch punctures said bag to permit electrolyte to escape from said baginto said sponge.

1. An electrode for electrocardiac machine comprising a metallic sheet,a handle to which said sheet is mounted, an electrical connectioninsulated from said handle and electrically connected to said metallicsheet, a closed foil bag having two sides, one side being mounted onsaid metallic sheet, an electrolyte in said bag, and a sponge connectedto the side of the bag opposite to the aforementioned side adhesivelyconnected on said metallic sheet, a retractable punch mounted on saidhandle adjoining said foil bag, and means connected to said punch formoving said punch through both sides of said foil bag, whereby saidpunch punctures said bag to permit electrolyte to escape from said baginto said sponge.